This is a follow-up question of How do I get default values of optional parameters?
From documentation, DefaultValue:
Gets a value indicating
There is a subtle but significant difference between "in the context of reflection" and "the reflection-only context". The "reflection only context" is referring to something very specific:
It is a way to load an assembly for examination only and has the distinct advantage of not requiring any dependent assemblies to be loaded or even to be present.
Since you appear to have every intention of executing some of the code you are reflecting, the reflection-only context would be of limited use to you.